Taper cutting attachment for lathes



Dec. 11, 1945. D. o. TRUBA ETAL V TAPER CUTTING ATTACHMENT FOR LATHES Filed Sept. 5, 1944 5 Sheets-Sheet 1 Inventors Fean 0. Traba 7" A .Zf'lnzer I'll z'ZZe-r M By @Mm Dec. 11, 1945. 0.0 TRUBA ETAL 2,390,627

TAPER CUTTING ATTACHMENT FOR LATHES 3 Sheets-Sheet 2 Filed Sept. 5, 1944 l nz'erztora Fear: 0.771150 Elmer Z'I, z'ZZer M B Z Dec. 11, 1945.' D. o. TRUBA ET AL 2,390,627 TAPER CUTTING ATTACHMENT FOR LATHES Filed Sept. 5, 1944 s Sheets-Shed 3 ill I unullll Patented Dec. 11, 1945 TAPER CUTTING ATTACHBIENT FOR LATHES Dean 0. Truba, South Gate, and Elmer T. Liller, Los Angeles, Calif.

Application September 5, 1944, Serial No. 552,754

3 Claims.

This invention appertains tonew and useful improvements in taper cutting attachment for lathes and more particularly to an improvement in our co-pending application Serial No. 470,618, filed December 30, 1942, and now Patent No. 2,372,916, granted April 3, 1945.

An important object of the invention is to provide an improved tailstock whereby the tailstook canbe setand the Work held at an off-center position to effect the cutting of tapers in work. 4 Another important object of the invention is to provide an adjustable tailsto-ck for performing taper work which can be readily adjusted and wherein micromic facilities are provided for minute adjustments.

Other objects and advantages of the invention will become apparent to the reader of the followmg description.

In the drawings:

Figure 1 represents a top plan view of the assembly.- I

Figure 2 isa face elevational view of the improved tailstock.

Figure 3 is a vertical sectional view through the improved tailstock.

Figure 4 is a fragmentary side elevational view.

Figure 5 is a fragmentary sectional detail view of protractor ring with its ring gear and the driving pinion for said ring gear.

Figure 6 is a section on line 66 of Figure 3.

Referring to the drawings wherein like numerals designate like parts, it can be seen that numeral 5 denotes the usual tailstock spindle of a lathe which is adapted to receive the usual detachable tailstock taper 6. Obviously, various sizes of tapers 6 may be employed, depending upon the size of the lathe upon which the improved tailstock is to be employed.

Numeral 1 denotes a cylindrical body having a central web 8 into which the taper 6 is screwed. This body 1 is stepped downwardly to provide a horizontal skirt 9 having threads on which a Vernier locking ring II i feedable, this ring being feedable against a Vernier ring 12 which has an outstanding wall l3 provided with an outwardly disposed and beveled rim I 4, slightly overlapping the cylindrical portion l of a protractor ring H5. The 'protractor ring I6 is secured to an annulus I! located therein and which is threaded at its periphery for threaded engagement with a taper locking ring l8, this ring having an internal flange l9 between which and a beveled annular head 28 on the body I a shim 2| is located.

Inside of the protractor ring I6 is a ring gear 22 with which a pinion 23 on a shaft 24 meshes.

The shaft is slidable in a cap structure which also has a recess into which the gear 213 can recede and thus be located without contact with the ring gear 22. The gear can be thus retained in out of meshed position through th use of a threaded nut 26 and a jamb nut 21 located on the threaded portion 28 of the shaft 24. Obviously, by rotating the shaft 24, with the gear 23 in mesh with the ring gear 22, adjustment of the protractor ring 16 is accomplished. This operation takes place only after the Vernier locking ring H has been loosened.

It can here be seen that a tailstock looking screw 38 is carried by ,the'skirt 9 of the hollow body 1. The screw 3!] is disposed through the skirt, and this contains a pin 3| which engages into the keywayfia of the spindle 5. (See Figure 3.) Other set screws 3E! coact with screw 30 to brace and secure the body 1 in concentric relation to spindle 5 and to secure the taper 6 in said spindle. The means for effecting an off-center disposi tion of work includes a transversely disposed block 32 carried by ring l6 and having a dovetail formation 32a thereon over which a dovetail channeled slide 33 is disposed.

The slide 33 has a groove therein for receiving a box extension 34 on the block 32. The slide 33 carries a nut 35 which is formed with a threaded opening for receiving an elongated feed screw 36.

The feed screw 36 has a reduced threaded portion 36a on which is a hand Wheel 3212, while on the other end of the shaft 36 is a reduced threaded extension 38 on which is a knurled hand wheel 23a. With respect to the shaft 36, the hand wheels 32b and 23a, these parts operate the same as the corresponding mechanism in our pending application Serial No. 470,618.

A stud 33 is secured to the face side of the slide 33 by Allen screws or the like 40, the projecting portion of this stud being threaded to engage internal threads in a cap 4| which has a tapered socket for receiving the'tapered shank is moved transversely it makes possible a scale reading of the offset amount when precision settings are not required. On the block 32 is secured a substantially right-angularly-shaped plate 46 having an upstanding pin 41 at a portion located over the slide 33. An upstanding pin 48 in the path of the plate 46 is provided on the slide 33. This assembly of parts constitutes a mechanism by which the center 42 may be set off-center to any desired micromic setting. The plate 46 which serves as a bracket for the 'micromic pin is stationary. The micromatic pin 48 moves along with the slide 43. It can be seen that by reading the distance between the pins 41, 48 with micrometers the amount of offset can be determined accurately.

A back center stop is composed of a bracket 49 on block 32 through which a screw 50 is feedable and this screw is provided with a skirted jamb nut 5|. This device prevents the slide 33 from moving back of a definite set center point.

A fixed nut 53 on the protractor ring l6 has a threaded shaft 54 disposed therethrough and in the path of aprotuberance 55 depending from the slide block 33. The screw 54, which is rotated by a knurled knob 56, in conjunction with the stop 55 make up a device for duplicate taper work and may be set at any predetermined amount of offset from a center.

A block 51 is attached to an external rib 58 carried by the taper locking ring [8 and movable in a circumferential slot 59 provided in the cylindrical portion l5 of protractor ring IS. A handle 7 60 is attached to block 51, and the intermediate portion of a leaf spring 6| is secured between the block 51 and rib 58. The ends of spring 6| bear on the periphery of the portion l5 of ring l6 beyond the ends of slot 59. When handle 60 is used to turn ring [6 and release the frictional engagement between the parts I9, 20 and 2 l, the parts I6 and I1 and the elements carried by part Hi can be freely turned relative to the parts 5, 6, I, 8 and 20.

By loosening screws 40, stud 39 may be shifted to adjust the ball center 42 to a centralized position, the stud 39 having apertures slightly invention, what is adjusting means, and means for rotating said carriage, said carriage consisting of an internal ring gear, said carriage rotating means including a hand rotated shaft and a pinion on said shaft meshing with the ring gear.

2. In a tailstock, a work center, micromatic adjusting means for off-center adjusting said center, a protractor carriage for said center and adjusting means, and means for rotating said carriage, said carriage consisting of an internal ring gear, said carriage rotating means including a hand rotated shaft and a pinion on said shaft meshing with the ring gear, said ring gear being shiftable to a position out of mesh with the ring gear.

3. In a tailstock, a work center, micromatic adjusting means for oiT-center adjusting said center, a protractor carriage for said center and adjusting means, and means for rotating said carriage, said carriage consisting of an internal ring gear, said carriage rotating means including a hand rotated shaft and a pinion on said shaft meshing with the ring gear, said ring gear being shiftable to a position out of mesh with the ring gear, said protractor being operative independently of the ring gear and shaft carried pinion.

DEAN O. TRUBA. ELMER T. LILLER. 

